<!DOCTYPE HTML>
<html><head>
    <meta charset="utf-8">
    <title></title>
    <style type="text/css">
body,html { color:black; background:white; font-size:12px; padding:0; margin:0; }
html {
  writing-mode: vertical-rl;
  text-orientation: sideways-right;
}

.grid {
  block-size: 60px;
  border: 2px solid green;
  position: relative;
}

span {
  position: absolute;
  background: lime;
  border: 1px solid black;
  box-sizing: border-box;
  inline-size: 20px;
  block-size: 20px;
}

.test1 .a {
  offset-block-start: 0;
  offset-inline-start: 20px;
  inline-size: 20px;
  block-size: 20px;
}
.test1 .b {
  offset-block-start: 20px;
  offset-inline-start: 20px;
  inline-size: 60px;
  block-size: 20px;
}
.test1 .c {
  offset-block-start: 0;
  offset-inline-start: 80px;
  inline-size: 60px;
  block-size: 40px;
}
.test1 .d {
  offset-block-start: 0;
  offset-inline-start: 0;
}
.test1 .e {
  offset-block-start: 20px;
  offset-inline-start: 0;
}
.test1 .d2 {
  offset-block-start: 0;
  offset-inline-start: 40px;
}

.test2 .a {
  offset-block-start: 0;
  offset-inline-start: 20px;
  inline-size: 60px;
  block-size: 20px;
}
.test2 .b {
  offset-block-start: 20px;
  offset-inline-start: 20px;
  inline-size: 20px;
  block-size: 20px;
}
.test2 .c {
  offset-block-start: 0;
  offset-inline-start: 80px;
  inline-size: 60px;
  block-size: 40px;
}
.test2 .d {
  offset-block-start: 0;
  offset-inline-start: 0;
}
.test2 .e {
  offset-block-start: 20px;
  offset-inline-start: 0;
}
.test2 .d2 {
  offset-block-start: 20px;
  offset-inline-start: 40px;
}

.test3 .a {
  offset-block-start: 0;
  offset-inline-start: 0;
  inline-size: 60px;
  block-size: 40px;
}
.test3 .b {
  offset-block-start: 40px;
  offset-inline-start: 20px;
  inline-size: 60px;
  block-size: 20px;
}
.test3 .c {
  offset-block-start: 60px;
  offset-inline-start: 0;
  inline-size: 60px;
  block-size: 40px;
}
.test3 .d { offset-block-start: 60px; offset-inline-start:60px; }
.test3 .e {
  offset-block-start: 20px;
  offset-inline-start: 60px;
}
.test3 .d2 {
  offset-block-start: 80px;
  offset-inline-start: 60px;
}

.test4 .c {
  offset-block-start: 0;
  offset-inline-start: 20px;
  inline-size: 60px;
  block-size: 40px;
}
.test4 .d {
  offset-block-start: 40px;
  offset-inline-start: 0;
}
.test4 .e {
  offset-block-start: 20px;
  offset-inline-start: 0px;
}
.test4 .d2 {
  offset-block-start: 40px;
  offset-inline-start: 20px;
}

.test5 .c {
  offset-block-start: 20px;
  offset-inline-start: 0;
  inline-size: 60px;
  block-size: 20px;
}
.test5 .d {
  offset-block-start: 0;
  offset-inline-start: 0;
}
.test5 .e {
  offset-block-start: 20px;
  offset-inline-start: 60px;
}
.test5 .d2 {
  offset-block-start: 0;
  offset-inline-start: 20px;
}

.test6 {
  offset-inline-start: 0;
  offset-block-start: 20px;
}
.test6d2 {
  offset-block-start: 20px;
  offset-inline-start: 140px;
}
.test6e {
  offset-block-start: 20px;
  offset-inline-start: 160px;
}
    </style>
</head>
<body>

<div class="grid test1">
<span class="a">a</span>
<span class="b">b</span>
<span class="c">c</span>
<span class="d">d</span>
<span class="d2">D</span>
<span class="e">e</span>
</div>

<div class="grid test2">
<span class="a">a</span>
<span class="b">b</span>
<span class="c">c</span>
<span class="d">d</span>
<span class="d2">D</span>
<span class="e">e</span>
</div>

<div class="grid test3" style="block-size:100px">
<span class="a">a</span>
<span class="b">b</span>
<span class="c">c</span>
<span class="d">d</span>
<span class="d2">D</span>
<span class="e">e</span>
</div>

<div class="grid test4">
<span class="c">c</span>
<span class="d">d</span>
<span class="d2">D</span>
<span class="e">e</span>
</div>

<div class="grid test5">
<span class="c">c</span>
<span class="d">d</span>
<span class="d2">D</span>
<span class="e">e</span>
</div>

<div class="grid test1">
<span class="a">a</span>
<span class="b">b</span>
<span class="c">c</span>
<span class="test6">d</span>
<span class="test6d2">D</span>
<span class="test6e">e</span>
</div>

</body>
</html>
